Hack saw



Patented Nov. I3, 1923.

JOHN A. ADELL AND ARTHUR HL STARR/ETT, OF ATHOL, M'ASSACHUSETTS, ASSIGNORS T THE L. S. STARR/ETT COMPANY, OF OF MASSACHUSETTS.

ATIOL, MASSACHUSETTS, A CORPORATION HACK SAXV.

Application led February To all ytf1/wm t may conc-era `Be it known that we, JOHN A. ADnLL and ARTHUR H. STARRETT, citizens of the United States, both residing at Athol, county of 5 Vitorcester, and Commonwealth of Massachusetts, have invented certain new and useful In'iprovements in Hack Saws, of which the following is a specification.

This invent-ion relates to hack saw frames, and particularly to such frames of extension type adapted to take blades of different lengths. In such devices it is desirable that the frame be so constructed as to render its manipulation easy, while maintaining simplicity of structure and freedom from projecting parts which might interfere with the manipulation of the saw or be fouled while it is in use.

Inasmnch as saw frames of this type usually provide for the tensioning of the blade, there has generally been a tendency upon the breaking of a blade or in the replacement of a worn blade of the frame to collapse or the parts thereof to be left adrift and dangle the new blade awkward and slow.

It is one object of the present invention, therefore, to provide a saw frame which while conforming in general to standard type will avoid the difficulties hereinbefore experienced. Ille accomplish these desired results first, by providing for control of the blade hangers so that they will retain posi# tion when not under tension; second, by providing a new structure in the frame for its adjustment; and third, by the general iinproveinent in various details of mechanical refinement which add to the utility, adaptability and convenience of the tool.

In the accompanying drawings, we show a li'orm. of 'saw' frame which not only well illustrates the principles of our inventionv1 but is in itself found satisfactory in use and well'adapted to the requirements of manuv facture upon a. commercial scale.

V Throughouttlie -specification and drawings lilrereference characters are corre spondingljvapplied, and in the drawings:

Fig isran elevation of a sectional liacl saw frameembodying the principles of our invention. Y

FigyII is an enlarged detal'of the coupling for the frame sections and particularly illustrating the self-locking construction of or turn, thus rendering the application of 3, 1921. serial no. 442,230.

the pawl for holding?)` the adjustment of the frame sec-tions.

F ig. III is a section on the line III- III of Fig. II.

Fig. IV is a detail section at the blade carrying' end of the adjustable frame section.

F ig. V is a detail view of the blade clamping spindle shown in Fig. IV, removed.

F ig. VI is a side view of the thimble shown in Fig. IV, removed.

F ig. VII is an end view of such thimble.

Fig. VIII is a detail section at the blade carrying end of the handle section of the frame, and showing the blade clampingl spindle at said end locked, and

Fig. IX is a similar view thereof and showing` said spindle released.

Our saw frame comprises a relatively stationary handle section l and an adjustable section 2. To the section l is fastened a tubular coupling` 3 within which the free end of the section 2 is adapted to be inserted and locked at selected positions of adjustment. The section 2 accordingly is provided alongr its upper face with a longitudinal series of notches t within which a locking pawl 5 pivoted between its ends at G in ears T formed on the coupling 3 is adapted to be selectively engaged. The pawl 5 is 1naintained normally engaged in a selected notch 4 by a coil spring, 8 interposed between the upper edge of the coupling 3 and the under face of the pawl heel. The spring` 8 is overw come when the user applies his thumb to the heel of the pawl to rock the pawl on its pivot and withdraw the toe thereof from a notch 4L.

The coupling 3 is a tube having tlat sides and rounded top and bottom edges. The top edge el said tnbc adjacent its forward end is notched as indicated at fi. Fig. Il, and lie'i'mnl said notch split and thc-porA tions thus separated turned out.\'ardly into the planes el" the side walls of the tube Vlo provide the` bearing; ears 'T im' the j iiawl 5 which lies between said and by them n;

The inner tace of the pawl heel asindicateifl at II, and thespring 8 is interposed betweensaidl evel Si and the bevel outer face of the notched portion 8. This construction not only results in a neatertinish, but permits the pawl 8 to be mounted closely adjacent the plane of the coupling` 3, and so mounted the pawl is protected against injury and against accidental disturbance of its setting.

The iframe sections 1 and 2 when coupled as shoivn in l? ig. I define a substantially Ushaped adjustable trame upon which blades Bot varying sizes may be removably clamped. At its lovver edge each iframe section accordingly is pro *ided with depending alined bearings t) and 1() within which are rotatably mounted blade clamping hangers or spindles 11 and 12. Said spindles are each reduced at their opposing ends, as indicated at 13 to provide'tlat seats for the ends of the blade B and said seats have inclined pins 1l adapted to detachably engage in slots 15 at 'the blade ends.

The spindle 1l of the handle section 1 is circuni't'erentially grooved between its ends, asI indicated at 1G, Fig. VIII, to receive a gravity detent 17, which is slidablymoi'inted in a vertically disposed recess 1S formed in the lower edge of the handle section behind the bearing 9. Near vits outer end said spindle is provided with a transverse pin 19 adapted to be selectively engaged in a circumerential series oi? notches 2O cut in the outer end of the bearing).

The spindle 12 of the adjustable 'traine section .2 beyond the dat seat portion 13 thereof is longitudinally grooved as indicated at 21, Figs. IV and V, and terminates in an outer threaded portion 22 which issi-mila'rly grooved as indicated at 23` groove 23 being a continuation of groove 21. The groove 21 is normally occupied by a blade spring 24: which is last at one end to a thim'ble 25 applied to the outer threaded end o1 the spindle beyond the hearing 10. The free end 'ot the 'spring is slightly outturned and when the blade B is clamped upon the said frame, said turned end lodges against the inner end of the bearing 10.

The inner end ot the thiinble is provided with'one or more locking projections 26 adapted to seat in a circumferential series of notches 27 cut. in the outer end ot the bearing 10. Beyond the thin'ible a Wing nut 28 is applied to the threaded portion 22 ot the spindle. In assembling, the thimble 25 is-applied to the outer end of the bearing 10, and the spindle l2 is inserted t-hrougl'i theV inner end oi" the bearingwith its groove 21 receiving the spring 24.. The nut 28 is then run onto the threaded end 22 of the spindle and set up against the thiinble 25.

The spindle 11 inserted through the bearing 9, the'detent 17 initially moving upwardly into its 'recess 1S and subsequently' dropping vinto the groove 16 to lock the spindle against longitudinal shifting movement in the bealingf.V

`With the spindles thus assembled, and with theframe sections adjusted to space the spindles a distance apart approximately the length oi'. the blade 'to be attached, 'the spindle 12 is adjusted longitudinally olf its bearing 10 by 'means of the Wing fnut 28 until the pins 14 of the spindles will enter the slots 15 ol the blade, and the blade is then strained -to tension and clamped by continued rotation o1" the nut. 28. Such ac tion seats the pin 19 in the notches'20 o' `the bearing 9 and the projections26 of the thiinble 25 in the notches 2T of the bearing The blade is released by rotating the nut i 28 in reverse direction to :permit the blade to be disengaged Lfrom the 'pins 111. In such release, the detent 1T prevents the spindle 11 from shitting longitudinally in its bear; ing 9, and the spring 211 prevents accidental dropping out ot' the thimble 25 from the bearing- 1() it the spindle 13 is removed, and also tends 4to keep the spindle 13 in place in the bearing il there is no saw blade to keep it under tension. It also tends to keep the spindle in its desired vertical position7 although the thimble 25 can be withdrawn and reversed. The spindle 1 2 may be removed trom its vbearing- `only 'by backing oit the nut 2S, and then sliding the spindle inwardly ltowards the opposite spindle 11 thus disen-gaging from the spring 24. The spindle 11 may be removed from its bearing 9 by knocking out the pin 19 and sliding the spindle vinwardly towards the opposite spindle 1'2, the jdetent17 movi-n-gI back into its recess in such Withdrawal.

Various modifications in the form and construction of my device may obviously be resorted to if Within the limits of the' appended claims.

What vve therefore claim and desire to secure by Letters Patent is:

1. In a saiv7 a trame having a spindle bearing, a blade clamping spindle 'adjustable in said bearing, a thiinble mounted on said spindle beyond fsaid bearing and inovabl'e intolocking engagement therewith-7 means adjustable on said spindle beyond said thinible for holding said thiinble in engagement With said bearing, afnd a blade spring disposed longitudinally of said spindle and fixed to said thiinble at one end and 1i-"siigag ing said bearing atits opposite end for maintaining lthe position of said spindle relative to said bearing Vvvhen the thi'gibl'e is, disengaged from the bearing and the yspindle releases. Y

2. Inv a savv7 a 1ra-me hav-ing a Vspindle bearing, a leiigitilily grocited blade clamping spindle adj able in said hearing, a tlilinble 1ii i1`ntedV on Said spindle beyd said bearing and movable intov leiing eirgage'me'nt therewith, means adjustable `on said spindle bevond said 'eh-natie for nele'- ing said thimble in engagement withV said bearing, and a blade spring disposed in said `grooveand fixed to saidrthi'nibgle at one 'end` and engaging said bearing at its opposite i ,evaso-3 end for maintaining the position of said spindle relative to said bearing when the thimble is disengaged from the bearing and the spindle released.

3. In a saw, a frame having a spindle bearing, a longitudinally grooved blade clamping spindle adjustable in said bearing and having a series of screw threads interseoting said groove, a thimble mounted on said spindle beyond said bearin and movable into .loc-king engagement tierewith, a nut adjustable along said threads of the spindle beyond said thinible for holding said thimble in engagement with said bearingr and a blade spring` disposed in said groove and fixed to said thimble at one end and engaging said bearing at its opposite end for maintaining the position of said spindle relative to said bearing when the thimble is disengaged from the bearing and the spindle released.

LL. In a saw, a frame having a fixed bearing and having a recess opening into said bearing, a blade carrying spindle movable in said bearing and having a circumferential groove between its ends, and a detent slidable in said recess and engageable in said groove to fix the position of the spindle in the bearing.

5. In a saw frame a spindle bearing, an adjustable blade supporting spindle in said bea-ring, athimble about said spindle and adjustably engageable therewith, and a resilient member detaehably connecting said thimble with said bearing and rictionally engaging said spindle to hold it against accidental dislodgment.

6. In a saw frame, a spindle bearing having an adjustable blade supporting spindle in said bearing, a thimble about said spindle and a resilient key rictionally interengaging said spindle and thimble and detachably engaging said barrel to prevent accidental dislodgment of the parts in the absence of an assembled blade.

In testimony whereof We affix our signa tures in presence of tWo Witnesses.

JOHN A. ADELL. ARTHUR H. STARRET T.

Vitnesses:

ERNEST W. TAYLOR, HARRY E. MAs'rERs. 

